Answer:
Mass = 18 g
Explanation:
Given data:
Number of molecules of Dicarbon hexahydride = 3.58 × 10²³ molecules
Mass of Dicarbon hexahydride = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
3.58 × 10²³ molecules × 1 mol / 6.022 × 10²³ molecules
0.6 mol
Mass of Dicarbon hexahydride:
Mass = number of moles × molar mass
Mass = 0.6 mol × 30 g/mol
Mass = 18 g
Molar mass of phosphorus (p) : 30.9 g/mol
1 mole P ----------- 30.9 g
x mole -------------- 2.3 g
30.9 * x = 2.3* 1
30.9 x = 2.3
x = 2.3 / 30.9
x = 0.07 moles
I think it’s I
Iodine has 53 protons and 74 neutrons
Answer:
9.1 KJ
Explanation:
First we must find the number of moles of HBr involved;
number of moles of HBr= mass of HBr/ molar mass of HBr
But molar mass of HBr= 80.91 g/mol
Given mass of HBr from the question= 20.1g
Hence;
Number of moles of HBr= 20.1 g/80.91g
Number of moles of HBr= 0.25 moles of HBr
If 2 moles of HBr has a heat of formation of 72.80KJ
Then 0.25 moles of HBr will have a heat of formation of 0.25× 72.80/2= 9.1 KJ
Therefore; 20.1 g of HBr will have a heat of formation of 9.1 KJ
The question is not clear
sorry